• 제목/요약/키워드: Water Transport

검색결과 1,907건 처리시간 0.026초

Probabilistic and spectral modelling of dynamic wind effects of quayside container cranes

  • Su, Ning;Peng, Shitao;Hong, Ningning;Wu, Xiaotong;Chen, Yunyue
    • Wind and Structures
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    • 제30권4호
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    • pp.405-421
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    • 2020
  • Quayside container cranes are important delivery machineries located in the most frontiers of container terminals, where strong wind attacks happen occasionally. Since the previous researches on quayside container cranes mainly focused on the mean wind load and static response characteristics, the fluctuating wind load and dynamic response characteristics require further investigations. In the present study, the aerodynamic wind loads on quayside container cranes were obtained from wind tunnel tests. The probabilistic and spectral models of the fluctuating aerodynamic loads were established. Then the joint probabilistic distributions of dynamic wind-induced responses were derived theoretically based on a series of Gaussian and independent assumption of resonant components. Finally, the results were validated by time domain analysis using wind tunnel data. It is concluded that the assumptions are acceptable. And the presented approach can estimate peak dynamic sliding force, overturning moments and leg uplifts of quayside container cranes effectively and efficiently.

일회통과 관류실험시 물의 수송 : 관류액의 종류와 삼투압의 영향 (Water Transport during the Single-pass Perfusion Experiments : Effects of Some Perfusates and Their Osmolality)

  • 이정화;이현주;용철순;오두만
    • 약학회지
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    • 제39권4호
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    • pp.411-416
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    • 1995
  • The single-pass perfusion experiments were performed in anesthetized rats to investigate the effects of perfusates and their osmolality on the water transport and to determine the correlation between the extent of water transport and the volume change of perfusate. Phenol red was used as a nonabsorbable marker. In normal rats, when perfused at a flow rate of 0.5 ml/min, 2-(N-rnorpholino) ethanesulfonic acid (MES) and S$\phi$rensen's phosphate buffers showed minimal net water transport as 0.125 and 0.173 %/cm of intestinal length, respectively. Hypotonic perfusate of 200 mOsm/kg of water and hypertonic perfusate of 400 mOsm/kg of water generated significant water transport compared with isotonic perfusate of 300 mOsm/kg of water. There was a linear correlation between the extent of water transport and the volume change of perfusate, suggesting that the volume change can be used as a measure of water transport.

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부직포 충전재의 수분투파성 (Water Vapor Transport Properties of Nonwoven Batting Materials)

  • 김희숙;나미희;김은애
    • 한국의류학회지
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    • 제22권1호
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    • pp.72-79
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    • 1998
  • Journal of the Korean Society of Clothing and Textiles Vol. 22, No. 1 (1998) p. 72∼79 The purpose of this study was to investigate the effects of geometrical structure and fiber type on the water vapor transport properties of nonwoven batting materials. Two types of fiber were used such as polyester and wool. Correlation between physical properties of nonwovens and water vapor transport rate was analyzed by Pearson Correlation. Steady and dynamic state water vapor transport properties were measured by absorption, evaporation and cobaltots chloride method respectively. The results were as follows: 1) In geometrical structure, thickness of nonwovens was effected on absorption and evaporation rate and air permeability was more influencing factor on water vapor transport rate than porosity. There were no decreasing of water vapor transport rate in hydrophilic fiber at high relative humudity. 2) The hydrophilicity of fiber affected steady and dynamic state water vapor permeabilities and wool nonwoven showed higher water vapor transport rate than polyester at high relative humidity. 3) Thickness showed higher correlation coefficient with water vapor transport rate than other physical properties of nonwovens.

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소셜네트워크분석(SNA)을 활용한 수상운송서비스 무역 네트워크 분석 연구 (A Study on International Trade of Water Transport Service using Social Network Analysis)

  • 박선율
    • 무역학회지
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    • 제47권3호
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    • pp.75-92
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    • 2022
  • This study aims to analyze the International trade network of Water transport service using Social Network Analysis for defining the status of Korean Water transport industry. This study use World Input-Output Table of Asian Development Bank from 2000 to 2020 and build the International trade matrix of Water transport service from that. Therefore, this study analyze Out-degree centrality, In-degree centrality and betweenness centrality of Korea and other main countries in the matrix of World Water transport industry. As a result, Korea rank above 10th in the all centralities and the total output also rank 8th in the world, therefore, this study show the importance of Korean Water transport industry in the world. However, Singapore has the highest centrality in the world, even though China has the largest Total output among 63 countries.

지구 온난화에 따른 물 수송 변화 (The Change of Water Vapor Transport due to Global Warming)

  • 오현택;김정우;신호정;최영진
    • 한국수자원학회논문집
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    • 제37권2호
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    • pp.109-119
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    • 2004
  • 이 논문에서 우리는 대기 대순환 모형을 사용하여 지구 온난화에 따를 육지 대기로의 물 수송 변화를 평가했다. 해양으로부터 육지로의 물 수송 변화량은 지구온난화에 따라 거의 연중 증가한다. 유라시아대륙의 물 수송량은 연중 170∼350${\times}$106 Mt/day 수준의 증가를 보인다. 아프리카로의 수송은 11월을 제외한 모든 달에 감소를 보이고 특히 8월과 9월에 -350${\times}$106 Mt/day의 최대 감소를 나타낸다. 유라시아와 아프리카를 제외한 다른 대륙들에의 수송은 $\pm$80${\times}$106 Mt/day 미만의 증가와 감소를 달에 따라 다르게, 그리고 불규칙하게 보인다. 지구온난화로 유라시아 대륙에로의 물 수송이 전체적으로 증가하지만, 이 대륙 안에 위치한 사막지역의 물 수송은 감소한다. 그러므로, 사막을 제외한 부분, 특히 몬순 지역에 증가 분이 집중될 것이고, 이러한 동아시아 몬순강화의 결과로 몬순지역에 상당한 가용수의 증가가 기대된다.

모직물의 수분율 변화와 구조에 따른 기공도 및 수분전달 특성변화 (Change of Porosity and Water Vapour Transport Properties of Wool Fabrics by the Change of Moisture Regain and Fabric Structure)

  • 김동옥;나미희;김은애
    • 한국의류학회지
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    • 제23권6호
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    • pp.820-828
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    • 1999
  • The purpose of this study was to investigate the changes of pore area and water vapour transport by the changes of moisture regain and fabric structure of wool fabrics, As specimens 4 worsted wool fabrics were used. The pore area were measured by image analysis method and dinamic vapour transport and water reisitance was determined by clothing-environment-body modelling system. The pore area was changed by the moisture regain of wool fabrics. The change of pore area was influenced by the yarn twist thread count and cover factor and the weave type. The water vapour transport was changed by the moisture regain. The change of water vapour transport was influenced by the change of pore aree which was determined by image analysis.

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Seasonal Volume Transport Variation and Origin of the Tsushima Warm Current

  • You, Sung-Hyup;Yoon, Jong-Hwan
    • Ocean and Polar Research
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    • 제30권2호
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    • pp.193-205
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    • 2008
  • A model of the current and seasonal volume transport in the East China Sea was used to investigate the origin of the Tsushima Warm Current (TSWC). The modeled volume transport field suggested that the current field west of Kyushu ($30^{\circ}-32^{\circ}N$) was divided into two regions, R1 and R2, according to the bottom depth. R1 consisted of the Taiwan Warm Current (TWWC) region and the mixed Kuroshio-TWWC (MKT) water region, while R2 was the modified Kuroshio water (MKW) region west of Kyushu. The MKW branched from the Kuroshio and flowed into the Korea/Tsushima Straits through the Cheju-Kyushu Strait, contributing 41% of the annual mean volume transport of the TSWC. The TWWC and MKT water flowed into the Korea/Tsushima Straits through the Cheju-Kyushu and Cheju Straits, contributing 32% and 27% of the volume transport, respectively. The maximum volume transport of the MKW was 53% of the total volume transport of the TSWC in November, while the maximum volume transport of the water in the R1 region through the Cheju-Kyushu Strait was 41% in July. Hence, there were two peaks per year of volume transport in the TSWC.

폐수중 액체막에 의한 페놀의 이동 (Transport of Phenol in Waste Water Through Liquid Surfactant Membrane)

  • 우인성;김병석;김윤선
    • 한국안전학회지
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    • 제5권3호
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    • pp.39-43
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    • 1990
  • The transport of phenol from waste water through the liquid surfactant membrane containing Aliquat 336 as a carrier was analyzed by a theoretical model. Extraction experiments was carried out to investigate the effect of process parameters, such as mixing intensity, concentration of sodium hydroxide in internal aqueous solution, and counter anions, and initial phenol concentration in waste water at $25^{\circ}C$. It was found that transport rate of phenol increased with increasing pH differents. The transport rate of phenol in waste water was influenced by counter anions.

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부직포 충전재의 구조적 특성이 수분전달 특성에 미치는 영향-단층구조와 이층구조 부직포의 비교- (The Effect of Geometrical Structure on the Moisture Transport Properties of Nonwoven Batting Materials)

  • 김희숙;나미희
    • 한국의류학회지
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    • 제24권6호
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    • pp.810-818
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    • 2000
  • The purpose of this study was to analyze the effect of geometrical structure on the moisture transport properties of nonwoven batting materials. Two types of nonwovens were used such as single and double layered nonwovens. Steady and dynamic state water vapor transport properties were measured by absorption, evaporation and cobaltous chloride method respectively. The results of this study were as follows: 1) Geometrical structure affected water vapor evaporation, but there were no differences between single and double layered nonwovens in moisture absorption. Thickness and air permeability were influencing factor on water vapor transport rate. 2) Directionality of double layered nonwoven was observed both in steady and dynamic state moisture transport. There were differences between upper and lower layer of double layered nonwoven both in moisture absorption rate and color change by cobaltous chloride method. 3) In dynamic state of water vapor transport rate, single layered nonwoven reached more rapidly at the established relative humidity. It was confirmed that geometrical structure affected water vapor evaporation and hydrophilicity of fiber affected moisture absorption because there were much more water vapor transport rate by evaporation than absorption within the same period of time.

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